--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/java/org/msgpack/util/android/PortedImmutableEntry.java	Sat Oct 18 15:06:15 2014 +0900
@@ -0,0 +1,87 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package org.msgpack.util.android;
+
+import java.io.Serializable;
+import java.util.Map;
+
+/**
+ * An immutable key-value mapping. Despite the name, this class is non-final
+ * and its subclasses may be mutable.
+ * 
+ * This class is ported from java.util.AbstractMap$SimpleImmutableEntry of
+ * https://github.com/OESF/OHA-Android-4.0.3_r1.0 (Apache License).
+ */
+public class PortedImmutableEntry<K, V> implements Map.Entry<K, V>, Serializable {
+    private static final long serialVersionUID = -4564047655287765373L;
+
+    private final K key;
+    private final V value;
+
+    public PortedImmutableEntry(K theKey, V theValue) {
+        key = theKey;
+        value = theValue;
+    }
+
+    /**
+     * Constructs an instance with the key and value of {@code copyFrom}.
+     */
+    public PortedImmutableEntry(Map.Entry<? extends K, ? extends V> copyFrom) {
+        key = copyFrom.getKey();
+        value = copyFrom.getValue();
+    }
+
+    public K getKey() {
+        return key;
+    }
+
+    public V getValue() {
+        return value;
+    }
+
+    /**
+     * This base implementation throws {@code UnsupportedOperationException}
+     * always.
+     */
+    public V setValue(V object) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override public boolean equals(Object object) {
+        if (this == object) {
+            return true;
+        }
+        if (object instanceof Map.Entry) {
+            Map.Entry<?, ?> entry = (Map.Entry<?, ?>) object;
+            return (key == null ? entry.getKey() == null : key.equals(entry
+                    .getKey()))
+                    && (value == null ? entry.getValue() == null : value
+                            .equals(entry.getValue()));
+        }
+        return false;
+    }
+
+    @Override public int hashCode() {
+        return (key == null ? 0 : key.hashCode())
+                ^ (value == null ? 0 : value.hashCode());
+    }
+
+    @Override public String toString() {
+        return key + "=" + value;
+    }
+}